... explosive gas mixture , 1A 2B IIC* 1.3 temperature group ,T1-T61.4 Ambient temperature,-30 ~ +501.5 degreeRelative humidity, ≤95%1.6 ... -proof telephone made of si-aluminium alloy die-casting, High temperature electrostatic pensu of its surface. Shell with dial-up keyboard ... etc in a phone,. well-known oversea brand components. High temperature screening tests..3.3 Seven channels in a telephone or ...